Nickel complex catalyst compositions

ABSTRACT

An olefin dimerization catalyst system formed from (1) an organoaluminum compound and (2) a normally solid nickel complex which is the coordination product of a nickel compound and a substantially hydrocarbon-insoluble complexing solid polymeric component. In one embodiment, an effective olefin dimerization catalyst is formed from (1) ethyaluminum dichloride and (2) a nickel coordination product of nickel dichloride and poly(2vinylpyridine) cross-linked with divinylbenzene.

I l United States Patent 11 1 1111 3,872,026 Dunn Mar. 18, 1975 NICKEL COMPLEX CATALYST 2433,22? 12/1323 g lagohon et al 252/430 x ,4 5,8 12 l uec 252/429 B X COMPOSITIONS 3,511,891 5/1970 Taylor et a] 252/429 B X Inventor: Howard E. Dunn, Mount Vernon, 3,558,517 1/1971 Hughes et al. 252/429 B lnd. 3,558,518 1/1971 Zuech 252/429 B 7 [7 Ass g ee ps ole C mp y, 3,592,869 7/1971 Cannell 252/4..9 B X Bartlesville, Okla. [22] Pl d Ma 0 19 3 Primary Examiner-Patrick P. Garvin 21 A 1..No.: 346 335 l I pp 57 ABSTRACT Related U.S. Application Data [62] Division of Ser No 884 35] Dec H 1969 Pat NO An olefin dimerization catalyst system formed from 3 737 474' i (1) an organoaluminum compound and (2) a normally solid nickel complex which is the coordination prod- 1 s CL 252 429 B 252/43 R 252/431 C uct Of a nickel compound and a substantially hydro- 252/431 N, 252/431 p 26O/683 15 D carbon-insoluble complexing solid polymeric compo- 51 Int. Cl B01j 11/84 one embodiment an effective Olefin dimerila- [58] Field of Search u 260/683 15 D; 252/429 Ba tion catalyst is formed from (1) ethyaluminum dichlo- 252/431 R 431 C 431 N 431 P ride and (2) a nickel coordination product of nickel dichloride and poly(2-vinylpyridine) cross-linked with [56] References Cited dlvmylbenzene' UNITED STATES PATENTS 11 Claims, N0 Drawings 3,096,385 7/1963 McConnell et al 252/431 P X NICKEL COMPLEX CATALYST COMPOSITIONS This is a divisional application of my copending application having Ser. No. 884,351, filed Dec. ll, 1969, entitled Olefin Dimerization with Nickel Complexes, now US. Pat. No. 3,737,474. V

This invention relates to a method for the dimerization of olefins. in another aspect, the invention relates to a method for the dimerization of olefins in the presence of a catalyst formed from an organoaluminum compound and a solid nickel complex.

Many processed have been developed for olefin dimerization. However, few of the processes have provided catalysts having high activity and high selectivity for the production of olefin dimers and yet are easily separable from the dimerization reaction mixture.

Therefore, it is an object of this invention to provide a method for the dimerization of olefins.

It is another object of this invention to provide catalysts for the production of olefin dimers.

Other objects, advantages and features of my invention will be apparent to one skilled in the art from the following disclosure and the claims.

I have found the C to C acyclic and cyclic olefins can be dimerized according to the process of this invention by contacting the olefin with a catalyst formed by the admixture of (1) an organoaluminum compound represented by the formula R",,A1X,,,in combination with (2) a solid complex of nickel, as subsequently de fined, where R is an alkyl, alkenyl, aryl, or cycloalkyl radical, or a combination thereof such as alkaryl or aralkyl radical, having from 1 to 12 carbon atoms, X is a halogen, n can be an integer l, 2 or 3, m can be or the integer l or.2, and the sum of n and m equals 3. I have further found that according'to this invention, a catalyst formed by the admixture of the two components disclosed above has a high selectivity for the production of dimers of olefins.

Specific examples of the organoaluminum component of the catalyst system are: methylaluminum dichloride, dimethylaluminum chloride, diethylaluminum bromide, ethylaluminum dibromide, triethylaluminum, phenylaluminum dibromide, vinylaluminum diiodide, tributylaluminum, dibutylaluminum fuoride, benzylaluminum dichloride, 4-tolylaluminum dichloride, dodecylaluminum dibromide, and thelike, and mixtures thereof such as methylaluminum sesquichloride. Presently preferred aluminum compounds are organoaluminum chlorides, particularly those containing radicals of the lower hydrocarbons such as methyl and ethyl.

The nickel complex component of the invention catalyst system is the coordination product of a nickel compound and a complexing solid polymer component.

The nickel compounds of the catalyst system are any of those which can be complexed with the complexing groups of the solid polymeric component. Specific examples of these nickel compounds are nickel salts of inorganic or organic acids, for example, nickel chloride, nickel bromide, nickel iodide, nickel acetate, nickel propionate, nickel nitrate, nickel sulfate, nickel phosphate, and the like. Also suitable are nickel compounds which are already complexed such as the aquo, tertiary phosphine, pyridine, ether, cyano, and the like, complexes of nickel. When soluble complexes such as these are contacted with the polymeric component, they will, at least partially, form the nickel-polymer complex desired.

E I E Loioi l ill ll .I

wherein each R is an aromatic or aliphatic radical having up to about 12 carbon atoms, preferably a saturated aliphatic radical having from 1 to 5 carbon atoms; the R groups can be either mono-. dior tri-valent as indicated by the structural formulas; and Q is nitrogen, phosphorus, arsenic, or antimony.

The polymeric chain can be copolymerized, if desired, with other polymerizable hydrocarbon monomers such as ethylene, propylene, styrene, butadiene, as well as di-functional olefins such as divinylbenzene which act as crosslinking agents and which greatly increase the molecular weight of the polymer. However, the polymer can contain at least 75, preferably at least 90, percent by weight of the repeating units shown above. The polymer can have any molecular weight ranging from that which is just sufficient to make the material insoluble in hydrocarbon solvents under the reaction-conditions up to several million depending upon whether crosslinking agents are employed.

The polymers described above can be conventionally prepared from corresponding monomers which contain the complexing functional groups Thus, the suitable monomers are those which, in addition to the complexing functional group, contaon 1 or more polymerizable olefinic groups such as a vinyl group, a vinylidene group, an a-methylvinyl group and the like. Some suitable monomers are 2-vinylpyridine, 4-vinylpyridine, 3-allylpyridine, 4-vinylidenepyridine, 3-isobutyl-5- vinylpyridine, di(3-butenyl)sulfide, ethylvinyl sulfide, acrylonitrile, 3-vinyl-5-dimethylaminotoluene, diethylallylamine, diphenylvinylarsine, cyclohexyldivinylstibine, dibenzylvinylphosphine oxide, maleic anhydride, 3,5-hexanedione-l-ene, 4-vinyl-l,2-benzene dicarboxylic acid, and the like, and mixtures thereof. Such monomers can be contacted, under polymerization conditions, with free radical-producing catalysts, for example, organic peroxides, azo-bis-alkylnitrile compounds or other conventional catalyst systems, including polymerizing irradiation, which have activity for polymerizing unsaturated monomers to solid polymers.

A preferred class of solid polymers are those prepared from monovinyl-substituted monocyclic pyridines containing a minor amount of polyvinylsubstituted aromatic compounds. This class of pyridine compounds is represented by g and the class of polyvinyl-substituted aromatic compounds represent ed by (CH2: H) 2-;

RIO-4 (CHi=CH)2-a matic compounds are 1,2-divinylbenzene, 1,4- divinylbenzene, 1,2,4-trivinylbenzene, 1,3- divinylnaphthalene, 2,4-divinylbiphenyl, 3,5,4-

trivinylbiphenyl, l,2-divinyl-3,4-dimethylbenzene, 1,5- ,6-trivinyl-3,7-diethylnaphthalene, l,3-divinyl-4,5,8- tributylnaphthalene, 2,2'-divinyl-4-ethyl-4'- propylbiphenyl, and the like and mixtures thereof. Divinylbenzene is preferred, including commercial divinylbenzene which is a mixture of isomers. Other comonomers, such as styrene, ethylvinylbenzene, as well as those comonomers previously mentioned, can also be present.

The polymer can be in any shape or size. Preferably, the solid polymer is sufficiently finely divided to provide a fixed catalyst bed or slurry catalyst operation, but not so fine as to make it difficult to separate the catalyst from the product.

The nickel-polymer complex is formed by merely contacting the nickel compound with the polymer in the presence ofa diluent in which the nickel compound is at least partially soluble. Such diluents are preferably nonaqueous and still more preferably are those nonaqueous diluents which cause some swelling of the polymer, thus improving the contacting of functional groups of the polymer with the nickel compound. Specific examples of such solvents are ethers, alcohols, glycol ethers, hydrocarbons, halogenated hydrocarbons, and the like, including mixtures of such solvents. Some specific solvents are methanol, tetrahydrofuran, benzene, cyclohexane, chlorobenzene, ethylene dichloride, monomethyl ether of ethylene glycol, and the like.

The proportion of nickel compound used to contact the polymer will generally be that which is sufficient to form nickel complexes on from about 10 to about lOO, preferably 10 to about 90, percent of the available sites on the solid polymer. The capacity of a given solid polymer to accept the nickel can vary, but can be readily determined by simple experimentation. For example, a solution of the nickel compound can be passed through a bed of the particulate polymer until the polymer is saturated. Analysis of the polymer of the effluent indicates the capacity of the polymer to accept and retain the nickel compound.

After the nickel compound is complexed with the solid polymer it can be washed with additional solvent to displace non-complexed nickel or to displace one solvent with another. If desired, the complexed solid polymer can be dried by moderate heating under reduced pressure to remove the residual solvent and other volatiles.

The catalyst system of the invention can be formed by combining the ingredients in a number of ways. One method is to prepare the nickel-polymer complex as described above and then to contact the dried solid with a desired quantity of the organoaluminum compound. The organoaluminum compound is preferably applied in an inert solvent such as a hydrocarbon or halogenated hydrocarbon solvent. With or without the removal of the solvent, the aluminum-nickel polymer complex can then be transferred to the reaction zone.

Another method of forming the catalyst system is to separately meter each of the three components, namely, the nickel compound, the polymer, and the aluminum compound, into the reaction zone such that the solid catalyst composition is formed in situ.

Still another method of forming the catalyst system is to add the nickel compound and the organoaluminum compound to the solid polymer in the presence of a suitable diluent such that a slurry is formed. This slurry then can be pumped to the reaction zone of a batchwise or continuous operation.

In still another method of forming the catalyst system, a slurry can be made from the solid polymer, the nickel compound, and a suitable solvent. The slurry then can be pumped into the reaction zone and contacted with the olefin before the addition of the organoaluminum compound. The components of the catalyst are usually combined in proportion in a range of 0.1 to 20, preferably about 1 to 10, moles of the organoaluminum compound per mole of nickel complexed to the polymer. Catalyst poisons in the system can be scavenged by employing even greater proportions of the organoaluminum component.

The dimerization can be carried out using a number of conventional contacting techniques. Thus, the solid catalyst system can be used as a mobile catalyst system either in the presence of a suitable solvent, as a catalyst slurry porcess, or in the absence of any diluent and in the gas phase, as a fluidized catalyst bed process. Any conventional contacting technique can be utilized for the olefin dimerization and batchwise or continuous operation can be utilized.

If desired, the solid catalyst can be formed in a fixed catalytic bed through which the feed olefin can be passed either with or without a diluent.

The olefins to which the present dimerization process is directed include cyclic monoolefins having up to 12 carbon atoms per molecule and acyclic monoolefins having from about 2 to 12 carbon atoms, inclusive, where the acyclic monoolefin can be a terminal or internal olefin, branched or unbranched, but preferably has no branching nearer than the 3-position to the double bond. Examples of suitable monoolefins which can be used according to the present invention are ethylene, propylene, butene-l, butene-Z, pentene-l, pentene-2, cyclopentene, cyclohexene, 3,4,5-trimethylcyclohexene, 3-methyl-butene-1, cycloheptene, hexene- 2, heptene-l, cyclooctene, 4,4-dimethylheptene-, decene-l, dodecent-l, and the like, and mixtures thereof. The presently preferred olefins are ethylene and propylene. Mixtures of olefin can be contacted with a catalyst to form codimers," for example, ethylene and butylenes react to form hexenes, propylene and butylenes react to form heptenes, etc. I

The dimerization of the olefin or mixture of olefins can take place at temperatures within the range of -50 to 150C, and preferably within the range of lto 100C. Normally, it is desirable to carry out the dimerization reaction under pressures ranging from atmospheric up to 2,000 psig, preferably 20-500 psig. The dimerization can be carried out in the presence ofa diluent such as that used for the catalyst preparation desired. The time of contact of theolefin with the catalyst for the dimerization of the olefin will vary depending upon the desired degree of conversion, but generally will be within the range from about 0.1 minutes to 22 hours, preferably to l2 Q ni 1utes. A I w u Ordinarily from about 0.00001 to about 0.1 mole of complexed nickel per mole of olefin feed is present in the reaction zone. u

After completion of the reactiom or aftef removal of the effluent from the reaction zone. the catalyst of the present invention can be conveniently removed from the product by simple filtration or decantation. The catalyst can be recycled, if desired, back to the reaction zone either with or without a fortifying amount of the organoaluminum compound.

The dimers produced and the dimerization of olefins can be used for many purposes. For example, olefin dimers such as propylene dimers can be employed to make oxo alcohols which are used in the preparation of plasticizers such as for plasticizing polyvinyl chloride resins. Also, propylene dimers can be cracked by conventional methods to make isoprene.

The advantages of this invention are further illustrated by the following example. The reactants and their proportions and other specific conditions are presented as being typical and should not be construed to limit the invention unduly. 7

EXAMPLE 1 Poly(2-vinylpyridine) powder was prepared at about 50-70from a 90:10 by weight mixture of 2- vinylpyridine and commercial divinylbenzene using azo-bis-isobutyronitrile as a catalyst yielding a heavily crosslinked solid polymer having a molecular weight in excess of one million.

Two grams of this powder were added to a 125 milliliter flask. To this flask was also added 30 milliliters of ethylene glycol monomethyl ether. To another flask was added 0.24 grams of nickel dischloride hexahydrate and milliliters of ethylene glycol monomethyl ether. When all of the nickel salt had dissolved, this solution was added to the flask with the polymer. it was then warmed with stirring for about 15 minutes and then filtered. The solid was then dried for four hours at 140C while at 0.1-0.25 mm. A dry, dark blue powder was recovered.

A 0.5 gram quantity of the above-prepared nickelcomplexed solid polyrner was charged into a dry 7 milliliters of a one molar solution of ethylaluminum dichloride and chlorobenzene was added. The reaction was allowed to proceed at essentially room temperature for about 45 minutes with stirring. An additional 3 milliliters of the ethylaluminum dichloride solution had been added after 10 minutes ofthe reaction period.

The reaction was stopped by the addition of 20 milliliters of water. The organic layer was decanted and distilled, yielding 18.3 grams of C olefins. A sample of the olefin dimer product was hydrogenated and then analyzed by gas-liquid chromatography showing the presence of 69.0 weight percent Z-methylpentane. 26.8 weight percent n-hexane, 3.4 weight percent of 2,3- dimethylbutane, and 0.8 weight percent 3- methylpentane.

This run demonstrates that the solid catalyst system of this invention is very effective for the dimerization of propylene to hexenes.

Although this invention has been described in considerable detail, it must be understood that such detail is for the purpose of illustration only and that many variations and modifications can be made by one skilled in the art without departing from the scope and spirit thereof.

I claim:

1. A catalyst system consisting essentially of (A) an organoaluminum compound having the formula R,, AlX,,, wherein each R" is an alkyl, alkenyl, aryl, cycloalkyl radical, or combination thereof, having from 1 to 12 carbon atoms, X is a halogen, n is l, 2, or 3, m is 0, l, or 2, such that 11 plus m equals 3, and (B) a normally solid nickel complex wherein said (B) normally solid nickel complex is the coordination product of a nickel compound and a complexing solid polymeric component, said nickel compound is a nickel salt of an acid selected from the group consisting of mineral acids, acetic and propionic acids, the amount of organoaluminum compound present being in the range of 0.1 to 20 moles per mole of nickel complexed with the polymer,

said complexing solid polymeric component is substantially hydrocarbon insoluble and is a polymer containing repeating units represented by C=O on wherein each R is an alkyl group having from 1 to 4 carbon atoms and the total number of carbon atoms in all R groups of any molecule does notexceed l2.

3. The catalyst system as defined in claim 2 wherein said complexing solid substantially hydrocarbon insoluble polymeric component is a copolymer containing at least 75 weight percent of said polymerized monovinylsubstituted monocyclic pyridine monomer and the balance is a copolymerized aromatic compound represented by wherein each R is an alky group having from 1 to 4 carbon atoms and the total number of carbon atoms in all R groups of any molecule does not exceed 12.

4. The catalyst system according to claim 2 wherein said polymeric component is poly(2-vinylpyridine).

5. The catalyst system according to claim 1 wherein said nickel compound is a nickel halide.

6. The catalyst system according to claim 5 wherein said nickel halide is nickel dichloride, and said organoaluminum compound is ethylaluminum dichloride.

7. The catalyst system according to claim 2 wherein said polymeric component further contains copolymerized ethylene, propylene, styrene, butadiene, or divinylbenzene.

8. The catalyst system according to claim 7 wherein said polymeric component contains copolymerized divinylbenzene.

9. The catalyst system according to claim 1 wherein said complexing solid substantially hydrocarbon insoluble polymeric component contains at least percent by weight of said repeating unit and said nickel salt is selected from the group consisting of nickel chloride, nickel bromide, nickel iodide, nickel acetate, nickel propionate, nickel nitrate, nickel sulfate, and nickel phosphate.

10. The catalyst system according to claim 3 wherein said polymer is poly(2-vinylpyridine) crosslinked with divinylbenzene, said nickel compound is nickel dichloride, and said organoaluminum compound is ethylaluminum dichloride.

11. The catalyst system according to claim 3 wherein said polymer is poly(Z-vinylpyridine) polymerized with divinylbenzene and further wherein the complexing solid substantially hydrocarbon insoluble polymeric component contains at least 90 percent by weight of 

1. A CATALYST SYSTEM CONSISTING ESSENTIALLY OF (A) AN ORGANOALUMINUM COMPOUND HAVING THE FORMULA R"N ALXM WHEREIN EACH R" IS AN ALKYL, ALKENYL, ARYYL, CYCLOALKYL RADICAL, OR COMBINATION THEREOF, HAVING FROM 1 TO 12 CARBON ATOMS, X IS A HALOGEN, N IS 1,2, OR 3, M IS 0, 1, OR 2, SUCH THAT N PLUS M EQUALS 3, AND (B) A NORMALLY SOLID NICKEL COMPLEX WHEREIN SAID (B) NORMALLY SOLID NICKEL COMPLEX IS THE COORDINATION PRODUCT OF A NICKEL COMPOUND AND A COMPLEXING SOLID POLYMERIC COMPONENT, SAID NICKEL COMPOUND IS A NICKEL SALT OF AN ACID SELECTED FROM THE GROUP CONSISTING OF MINERAL ACIDS, ACETIC AND PROPIONIC ACIDS, THE AMOUNT OF ORGANOALUMINUM COMPOUND PRESENT BEING IN THE RANGE OF 0.1 TO 20 MOLES PER MOLE OF NICKEL COMPLEXED WITH THE POLYMER, SAID COMPLEXING SOLID POLYMERIC COMPONENT IS SUBSTANTIALLY HYDROCARBON INSOLUBLE AND IS A POLYMER CONTAINING REPEATING UNITS REPRESENTED BY :
 2. The catalyst system according to claim 1 wherein said complexing solid substantially hydrocarbon insoluble polymeric component is polymerized monovinyl-substItuted monocyclic pyridine monomer represented by
 3. The catalyst system as defined in claim 2 wherein said complexing solid substantially hydrocarbon insoluble polymeric component is a copolymer containing at least 75 weight percent of said polymerized monovinyl-substituted monocyclic pyridine monomer and the balance is a copolymerized aromatic compound represented by
 4. The catalyst system according to claim 2 wherein said polymeric component is poly(2-vinylpyridine).
 5. The catalyst system according to claim 1 wherein said nickel compound is a nickel halide.
 6. The catalyst system according to claim 5 wherein said nickel halide is nickel dichloride, and said organoaluminum compound is ethylaluminum dichloride.
 7. The catalyst system according to claim 2 wherein said polymeric component further contains copolymerized ethylene, propylene, styrene, butadiene, or divinylbenzene.
 8. The catalyst system according to claim 7 wherein said polymeric component contains copolymerized divinylbenzene.
 9. The catalyst system according to claim 1 wherein said complexing solid substantially hydrocarbon insoluble polymeric component contains at least 90 percent by weight of said repeating unit and said nickel salt is selected from the group consisting of nickel chloride, nickel bromide, nickel iodide, nickel acetate, nickel propionate, nickel nitrate, nickel sulfate, and nickel phosphate.
 10. The catalyst system according to claim 3 wherein said polymer is poly(2-vinylpyridine) crosslinked with divinylbenzene, said nickel compound is nickel dichloride, and said organoaluminum compound is ethylaluminum dichloride.
 11. The catalyst system according to claim 3 wherein said polymer is poly(2-vinylpyridine) polymerized with divinylbenzene and further wherein the complexing solid substantially hydrocarbon insoluble polymeric component contains at least 90 percent by weight of said poly(2-vinylpyridine). 